Thermal decomposition and kinetics of electrically controlled solid propellant through thermogravimetric analysis

The thermal decomposition behavior of electrically controlled solid propellant (ECSP) with hydroxyl ammonium nitrate as oxidizer and polyvinyl alcohol as binder was investigated through thermogravimetric analysis and differential scanning calorimetry coupling technology at the heating rates of 15, 20, 25, 30, and 35 K min(-1) in nitrogen. Results indicated that the T-initial and T-max values of the thermal decomposition of ECSP increase with heating rates. The activation energy E-alpha from the results of TG data at various heating rates was calculated by model-free isoconversional Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira-Sunose (KAS) methods. The activation energies obtained through the FWO method were close to those obtained through the KAS method, and the values for activation energy were located between 42.82 and 48.49 kJ mol(-1). An appropriate reaction mechanism conversion model for ECSP was determined by Malek and Coats-Redfern methods. Thermal decomposition kinetics of the ECSP obeyed the random nucleation and subsequent growth model, called Avrami-Erofeev function.